Grate for furnaces.



PATENTED JULY ll, 1905.

A. WILKINSONs GRATE FOR FURNAGES.

PPLIOATION FILED AUG. 8.1904* 2 SHEETS-SHEET l.

J LH Q E,

KNKKKKKNNN No. 794,575. PATEN'I'ED JULY Il, 1905.

A. WILKINSON.

GRATE FOR FURNACES.

APPLICATION FILED AUG. 8,1904.

2 SHEETS-SHEET 2,

UNTTED STATES Patented July 11, 1905.

PATENT OEEICE.

ALFRED WILKINSON, OF BRIDGEPORT, PENNSYLVANIA, ASSIGNOR TO 'l WILKINSON MANUFACTURING` COMPANY, OF BRIDGEPORT, PENN- SYLVANIA, A CORPORATION OF PENNSYLVANIA.

GRATE FOR FURNACES.

SPECIFICATION forming part of Letters Patent No. 794,575, dated July 11, 1905.

Application filed August 8, 1904. Serial No. 220,008.

To rif/U whom, 'if nto/y con/cern.-

Be it known that I, ALFRED WILKINSON, a citizen of the United States, residing in Bridgeport, Pennsylvania, have invented certain Improvements in' Grates for Furn aces, of which the following is a specification.

My invention consists of certain improvements in the furnace forming the subject of my'previous Letters Patent Nos. 480,588, 541,405, and 541,448, the object of my present invention being to preserve the desired close fit of the reciprocating grate bars against one another without interfering with their free movement. This object I attain in the manner hereinafter set forth, reference being had to the accompanying drawings, in which-y Figure 1 is a view, partly in side elevation and partly in longitudinal section, of suflicient of a steam-boiler furnace to illustrate my present invention. Fig. 2 is a transverse section of the same on the line a a, Fig. 1, with the grate-bar-reciprocating mechanism omitted. Fig. 3 is a face view of one of the cheek-plates of the grate. Fig. 4 is a longitudinal section of the same on the line b b, Fig. 3 and Fig. 5 is a similar view illustrating a modification of the invention.

So far as the grate itself is concerned it is substantially similar to those previously patented and consists of hollow bars 1, mounted at the lower end upon a hollow supportingbar 2 and at the upper end upon a similar hollow bar 3, the upper face of each bar throughout the greater portion of its extent being stepped and the vertical faces or risers of each step being perforated, so as to form twyers,from which jets of air or air and steam are projected into the mass of fuel lying upon the grate in order to effect combustion of thev same, the ,air being caused to enter the hollow bars in any desired manner-as, for instance, by means of a steam-pipe having nozzles 4, one of which projects into the upper end of each grate-bar. Reciprocation of the grate-bars is effected by means of a rockshaft 5, having arms, which are connected by links 6 to thegrate-bars. In the operation of furnaces of this class some difficulty has been experienced, for if the grate-bars do not fit snugly to each other the products of combustion are likely to be forced down between the grate-bars into the ash-pit, whereas if the grate-bars do fit snugly when cold their expansion when heated is likely to cause them to jam and interfere with their proper reciprocation by the power mechanisn employed for that purpose. In order to overcome this objection, I so construct the grate-bars that they will fit snugly to each other, but not to the cheek-pieces 7, which are carried by the side walls of the furnace structure, each of these cheek-pieces being provided with a yielding contact-bar 8, which is normally projected by some resilient means-such, for instance, as the spring 9, Fig. 4-so that while it will normally press firmly against the adjoining side of the outermost grate-bar on that side of the furnace it can yield and slide inwardly into the hollow cheek-piece 7 when sufficient pressure is eX- erted upon it, such as will be caused by the lateral expansion of the grate-bars when the same become heated.

While I prefer to use a spring as a means of projecting the bar 8, other resilient means may be employed. For instance, the bar may be connected to one or more rods 20, each provided with a piston adapted to a cylinder 21, located in the hollow cheek-piece and receiving air, steam, or other fluid under pressure from a pipe 22, and while I prefer to provide each of the cheek-pieces of the furnace with a resilient contact-bar of the character described, but one of said cheek-pieces may be thus provided, if desired.

The hollow boX portion of each cheekpiece has in the bottom one or more openings 10, which communicate with a chamber l0a formed in the sidewall of the furnace and discharging into the ash-pit, so that any fine ashes or other foreign matter finding its way into the hollow cheek-piece will escape therefrom into the chamber 10:L and thence into the ash-pit and will not interfere with the free movement of the bearing-bar.

At the base of the reciprocating grate-bar structure is a dead-plate 11, consisting of a plate or frame having in its upper face cells iilled with fire-brick or other refractory material, this dead-plate being supported upon flanges or brackets formed, respectively, upon the bar 2 and upon a transverse bar 12 arallel therewith and suitably protected from the heat by means of a block 13, of refractory material. From the bar 12 to the bridge-wall 14 extends a plate 15, which is slidably mounted in suitable guides'on the side walls of the furnace, so that it may receive the ashesl pushed from the dead-plate 11 or may be withdrawn by means of a suitable handle 16, so as to dump said ashes into the ash-pit, thus providing a convenient means of discharging the ashes at suitable intervals without causing prolonged communication between the ash-pit and combustionchamber except such as may be effected through the hollow grate-bars and the lower supporting-bar 2 when forced draft is employed.

Having thus described my invention, I claim and desire to secure by Letters Patent- 1. The combination of a grate having reciprocating bars disposed side by side and free to move laterally, one in respect to another, with a resiliently-mounted contactbar for imparting lateral pressure to said grate-bars., substantially as speciiied.

2. The combination of a grate having reciprocating bars'dis osed side by side and free to move lateral y, one in respect to another, with a resiliently-mounted contactbar at each side of the grate for imparting lateral pressure to said grate-bars, substantially as specified. i

3. The combination of a furnace having reciprocating grate-bars disposed side by side and free to move laterally, one in respect to another, with a cheek-piece having la resiliently-mounted contact-bar guided therein and serving by contact with a side grate-bar of the series to impart lateral presuie to said grate-bars, substantially as speci- 4. The combination of a grate having a series of reciprocating bars disposed side by side, with a cheek-piece having a chamber therein communicating with the ash-pit, and a contact-bar mounted in said chamber and combined with resilient means for projecting it, whereby it presses against the side gratebar of the series and serves to impart lateral pressure thereto, substantially as specified.

5. The combination of a grate consisting of a series of reciprocating bars, a recessed cheek-piece having slidably mounted therein a contact-bar for pressing against a side grate-bar of the series, and imparting lateral pressure thereto, and a spring contained in the recess of the cheek-piece and acting upon said contact-bar to project the same, substantially as specified.

In testimony whereof I have signed my nameto this specification in the presence of two subscribing witnesses.

ALFRED WILKINSON.

Witnesses z WALTER CHIsM, Jos. H. KLEIN. 

